So when people write SCPs, they tend to write very interesting yet rather deadly properties. That said, why should the Foundation keep certain things if all they do is kill? I understand that studying them makes a good excuse, but what if something is basically just a mindless killing machine? Why study these things if they are of no use but just to endanger personnel? Past SCPs have had this trait, and they were decommissioned and neutralised. Even with 682, it seems as though we just want to kill it rather than study it, and with good reason- it is worth more to kill it than study it and let destroy countless lives. I'm sure this is in some essay somewhere and I'm just stating the obvious, but I think people should consider this when writing SCPs.

In short, should people consider why their SCP should not be destroyed and Foundation resources should be devoted to it as to avoid repeats of OTP useless monsters?

The Foundation doesn't destroy SCPs (decomms are not something that we do anymore).
As such, it is absolutely unnecesary to consider this, as the answer more or less never changes1.
This does not, however, mean that a simple killing machine will be successful as an article.

Footnotes

1. An exception, of course, for looking to neutralize objects that might end the world in some manner, but that is a far different matter than things that 'just kill'.

Theoretically, one should consider everything when creating a skip. Everything.

That said, yes. Generic murdermonsters are not currently fashionable to begin with, but we its the GOC's territory to smash skips back into their base components, dust and ketchup. You'd be better off channeling that destructive creativity into neutralizing the non-essential non-anomalous byproducts of skips. We might not blow up skips but we certainly go about getting rid of the things they spew out, like books infected by some memetic skip, for example. I don't think burning those books will elicit any "that's not how the Foundatiok operates" complaints.

I've seen a few threads about, "Why does the Foundation Y around and not just destroy it?"

From a story stand point, it's because it's boring to kill off the dangerous subjects. It puts the power back into the Foundation, into mankind, when otherwise they'd always have the thing to fear. Same as why the Joker will never die in Batman.

From an in-universe point, sometimes killing something costs too much, or makes it worse. (a great story on that can be found here with SCP-1609)

Another in-universe point often brought up, is that we keep them around so we can at least try to learn something, so if they ever face something like it again, they can be prepared. If they killed SCP-096 right away, they might never had discovered that an artist's depiction the subject's face is safe to view. The real life example would be keeping deadly diseases for study.